The invention relates to a screwdriver for bone screws, having a handle and rotationally fixedly held thereon a shaft, the free end of which has a non-circular cross section and is insertable in a positively locked manner in a non-circular receiving opening in the head of a bone screw, at least one expander element being mounted so as to be displaceable in the longitudinal direction in the shaft and so as to slide, when displaced in the longitudinal direction, along a slide surface in the area of the free end of the shaft in such a way that it projects laterally over the contour of the shaft.
Such a screwdriver is described in DE 100 42 424 C2. With this screwdriver, the shaft can be releasably connected to the bone screw in a simple way by advancing the expander element, so that the bone screw is held at the free end of the shaft and can be taken to the intended point of application.
In the known screwdriver, the expander element is advanced by means of a sleeve which is rotatably mounted on a thread of the shaft. The object of the invention is to so construct a generic screwdriver that the advancing and retracting of the expander element are simpler than with the known screwdriver.